Derrick construction



A. D. RHODES DERRICK CONSTRUCTION July 4, 1939.

Filed July 19, 1938 k a F INVENTOR. 44e0/v .0. ,QHODES, W

ATTO

Patented July 4, 1939 UNITED STATES PATENT OFFICE DERRICK CONSTRUCTION Application July 19, 1938, Serial No. 220,050

8 Claims.

My invention relates to derrick structures for oil, gas, or similar wells and has particular reference to a derrick construction designed to facilitate the handling of long lengths of drill pipe, well casing, or similar material.

In drilling wells of this class it is common practice to provide a derrick of suitable height to accommodate the handling of drill pipe, casing tubing and other pipes used in the drilling of the Well, and for producing oil therefrom. For example, at present it is usual to construct a derrick substantially 135 feet high, provided with suitable hoisting devices for handling drill pipe in approximately 80 foot sections known as fourbles, said fourbles comprising four lengths of standard drill pipe of about twenty feet each coupled to ether as a unit.

In order to allow the drill pipe to be placed inside the derrick after the derrick is erected, it is the current practice to provide a window on one side approximately twenty-four feet high. While this is sufficient to allow the drill pipe to be drawn into the inside of the derrick in twenty foot lengths, it is not high enough to allow the pipe to be taken in or withdrawn in longer lengths. This therefore requires that the individual lengths be assembled into fourbles after they are placed within the derrick and that the fourbles be dismantled before the drill pipe can be removed from the derrick.

It is also current practice to move the drill pipe from a completed well to one which is just starting. Although there are conveyances avail-' able which can transport the drill pipe from one location to another in fourble lengths, it is necessary, because of the small window openingsavailable in the derricks, to disconnect the drill pipe sections, remove them from the derrick a piece at a time, place them within the new derrick one length at a time, and reconnect.

The same condition exists with respect to well casing. Casing can now be obtained in very long lengths, such as welded up lengths of casing approximately 80 to 90 feet, but because of the restricted window openings, such casing must be installed in short lengths, thus increasing the cost of such installation through the great number of joints which must be made inside the derrick over that required if it were possible to use the long lengths, or a plurality of short lengths welded into long units or sections before entry into the derrick.

It is therefore the primary object of my invention to provide a unique derrick construction providing a window in one side thereof of sufficient height to allow long sections of drill pipe, casing, or other material to be placed within the derrick.

It is another object of my invention to provide a derrick of the type described and to provide novel bracing to prevent said long window opening from weakening the derrick structure.

It is an additional object of my invention to provide readily removable girts across the said window opening to further increase the strength of the derrick tower for sustaining the loads encountered during the actual drilling operations.

Other objects and advantages will be apparent from a study of the following specifications, read in connection with the accompanying drawing, wherein:

Fig. 1 is an elevation of the window side of a derrick constructed in accordance with my invention showing the aforementioned removable girts in place.

Fig. 2 is an elevation similar to Fig. 1 showing the form the derrick assumes upon removal of the aforementioned girts.

Fig. 3 is a sectional plan view taken along the line III--III of Fig. 1 illustrating the manner in which additional bracing may be added to the derrick to compensate for the weakening effect of the large window.

Fig. 4 is a fragmentary sectional elevation taken along the line IV-IV of Fig. 3, illustrating in detail one method of providing readily removable girts in accordance with my invention.

Referring to the drawing, I have illustrated in Figs. 1 and 2 one side of a derrick tower including leg members 2 which are erected on a suitable foundation at the corners of a derrick floor 3. The leg members 2 are tied together by a plurality of horizontal girts 4 and a system of diagonal braces 5. These structural members forming the derrick tower may be attached to each other in any suitable manner as by riveting, bolting, or welding. Equipment carried by the derrick tower includes a crown platform or water table 5 for supporting the upper portion of the hoisting equipment, a gin pole I for handling such equipment, and a fourble or quadruple platform 8. The fourble platform 8 is located the proper distance above the derrick floor to permit a workman standing thereon to readily manipulate the drill stands, casing stands, or tubing stands when such pipe is connected up in fourbles.

In addition to the structure just described, I provide in the derrick tower of my invention an elongated window area 9 defined by side frames I 0 and a rope-guard H extending between the upper ends of the side frames Ill. The ropeguard H is preferably constructed along conventional lines and constitutes a cast or prefabricated member providing a smooth and rounded, downwardly directed surface against which rope sand lines, or other hoisting cables may run enever these cables are attached to objects disposed a considerable distance away from the derrick floor, the smooth surface provided by the rope-guard ll preventing chafing or damaging of the cable during such hoisting operations. The rope-guard ii is preferably located sufliciently far above the derrick floor, for example 73 feet from the derrick floor, to allow fourbles to be readily drawn in through said window area 8 into the interior space enclosed by the derrick tower. The side frames l0 and the rope-guard ll may be rigidly tied in to the rest of the derrick structure by half-girts l2 and diagonal braces l3 which may be secured in tower to compensate for said window area. As

shown in Fig. 3, I have enlarged and strengthened the girts on the sides of the derrick adjacent the side which includes the window area by providing girts H which may be stronger than the previously described girts Land which are arranged to extend outwardly beyond the leg members 2 on the window side. There is also provided a system of horizontal diagonal bracing which includes a brace l5 attached to the projecting end of the side girt I4 and extending to the 'window side frame l0 where it is attached to the side frame l0 and the half-girt II.

It is readily seen that by using this novel construction of my invention, the leg members 2,.the side frames HI, the girts i2 and I4, and the brace member l5 cooperate to form a rigid structure which will transmit to the remaining three sides of the derrick tower the torsional stresses induced in the window side by suspending a heavy load from the crown platform 6.

In order that the normal strength of the derrick tower during normal drilling operations will not be impaired in any manner. whatsoever by the window opening 9, I have provided, as illustrated in Figs. 3 and 4, a system of readily removable girts l6 and another rope-guard II, which may be quickly and easily installed whenever the window is not being actively used for -the passage of pipe into or out of the derrick.

' in the same manner in the position shown in Fig.

placed within or removed from the derrick in 1 and thus provide a smaller V window as in the conventional derrick for handling short sections of material.

It will. therefore be observed that I have provided a derrick tower of great strength and rigidity, suitable for the drilling of deep wells such as oilor gas wells, and that I have provided, by means of a novel construction, an elongated windowof sufllcient length to allow drill pipe, well casing, or other material to' be economically long lengths, thereby materially reducing the cost of handling this class of material.

While I have shown and described the preferred embodiment of my invention, I do not desire to be limited to. any of the details of construction shown herein, except as defined in the appended claims.

I claim:

1 In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening defined by said base, a horizontal top, and auxiliary frames lying between and extending upwardly in the plane of two of said legs, said window opening extending upwardly from said base a distance approximately equal to one-half the height of the derrick, and bracing means for attaching said frames to said adjacent legs.

2. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening defined by said I base, auxiliary side frames lying between and extending upwardly in the plane of two of said legs, and means interconnecting the upper ends of said side frames; and bracing means for attaching each of said side frames to an adjacent leg including girt members secured to each of a pair of adjacent legs and extending beyond the associated leg adjacent saidside frame, a brace member attached to said side frame and to said adjacent leg, and a member-attached to said side framev and to the extending end of said girt member.

3 In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening defined by said base, a horizontal top, and side frames lyi b tween and extending upwardly in the plane of two adjacent legs; bracing means for attaching said side frames to said adjacent legs; girt members extending between said side frames and across said window opening; and means for detachably securing said girt members to said side frames.

4. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to eachother; a window opening defined by said base, side frames lying between and extending upwardly in the plane of two of said' legs, and means interconnecting the upper ends of said side frames; bracing means for attaching each of said side frames to an adjacent leg consisting of a girt member attached to each of a pair of adiacent legs and extending beyond said leg adjacent said side frame. a brace member attached to said side frame and to said adjacent leg, and a member attached to said side frame and to the extending end of said girt member; connecting members extending between said side frames and across said window opening; and means for detachably attaching said connecting members to said side frames.

5. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening disposed between two adjacent legs and having a vertical height substantially equal to or in excess of onehelf e total height of the derrick; andauxiliary bracing means associated with each of said adjacent legs for bracing said legs against movement in the plane of said window opening.

6. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening disposed between two adjacent legs and having a vertical height substantially equal to' or in excess 01' onehalf the total height of the derrick; and auxiliary bracing means associated with each of said adjacent legs for bracing said legs against movement in the plane of said window opening, said auxiliary bracing means including an upwardly extending auxiliary frame member disposed in the plane of the window opening, and lateral and diagonal bracing interconnecting said frame member with the adjacent leg.

'I. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening disposed between two adjacent legs and having a vertical height substantially equal to or in excess of onehall. the total height of the derrick; auxiliary bracing means associated with each of said ad-" Jacent legs for bracing said legs against movement in the plane of said window opening; and horizontally extending bracing means associated with said auxiliary bracing means for preventing movement of said auxiliary bracing means in a plane transverse to the plane of the window opening.

8. In combination with a derrick tower including a base, legs extending upwardly from said base, and lateral and diagonal bracing for holding said legs in fixed spaced relationship relative to each other; a window opening defined by said base, auxiliary frames lying between and extending upwardly in the plane of two of said legs, and means interconnecting the upper ends of said side frames, said window opening extending upwardly from said base a distance approximately equal to one-half the height of the derrick, and

- bracing means for attaching said frames to said adjacent legs.

AARON D. RHODES. 

